The present invention relates to a silver halide photographic lightsensitive material which is excellent in color reproduction and graininess. More particularly, the present invention relates to a silver halide photographic lightsensitive material which contains a novel compound capable of rapidly trapping developing agent oxidation products.
The method of forming color images by first exposing a silver halide color photographic lightsensitive material and subsequently processing the exposed material with a color developing solution containing a developing agent of an aromatic primary amine, is well known for long. In this method, generally, the subtractive color processes are employed for color reproduction, and use is made of silver halide emulsions which are selectively sensitive to blue, green and red, in which agents for forming respectively complementary yellow, magenta and cyan color images (couplers) are contained.
With respect to this color forming method, it is known to add a compound capable of effectively trapping developing agent oxidation products in order to avoid such problems that fogging and graininess deterioration are caused by reactions between developing agent oxidation products produced in excess and couplers and that produced developing agent oxidation products are diffused into other layers to thereby bring about color turbidity.
Redox compounds are known as providing such a trapping agent for developing agent oxidation products, which redox compounds include, for example, ballasted hydroquinone (1,4-dihydroxybenzene) compounds described in U.S. Pat. Nos. 3,700,453 and 4,732,845, ballasted gallic acid (1,2,3-trihydroxybenzene) compounds described in U.S. Pat. No. 4,474,874, ballasted sulfonamidophenols described in U.S. Pat. Nos. 4,205,987 and 4,447,523, ballasted resorcinol (1,3-dihydroxybenzene) compounds described in U.S. Pat. No. 3,770,431 and hydrazide compounds described in U.S. Pat. No. 5,230,992, Jpn. Pat. Appln. KOKAI Publication No. (hereinafter referred to as JP-A-) 4-238347 and JP-A-8-240892. However, it is very difficult for these redox compounds to be excellent in both capability of trapping developing agent oxidation products (hereinafter referred to as "activity") and stability. Redox compounds with high activity have a drawback in that, when stored for long, they adversely affect the silver halide emulsion to thereby cause fogging and disorder of gradation. On the other hand, redox compounds with enhanced stability suffers from a lowering of activity. Moreover, it is not less frequent that such redox compounds per se form colored residue by trapping developing agent oxidation products.
As other forms of trapping agents for developing agent oxidation products, there are known systems utilizing coupling reactions, such as colorless compound forming couplers which couple with developing agent oxidation products to thereby form substantially colorless compounds as described in, for example, U.S. Pat. No. 3,876,428, JP-A-50-150434 and Jpn. Pat. Appln. KOKOKU Publication No. (hereinafter referred to as JP-B-) 57-51662 and outflowing dye forming couplers which form water-soluble dyes by coupling substantially not to thereby contribute to image formation as described in, for example, JP-A's-59-171955, 1-129252 and 6-138612. However, the former colorless compound forming couplers have a drawback in that the activity thereof is so low that a large amount of colorless compound forming coupler must be used for exerting the desired effect. On the other hand, the latter outflowing dye forming couplers, although both activity and stability can be relatively easily attained by optimizing the coupler nucleus and split-off groups thereof, have the danger of contaminating the processing solutions because of the outflow of formed dyes into the processing solutions. This contamination of the processing solutions is unfavorable in these days in which the reduction of replenisher for the processing solutions is being demanded. Further, the structure of the above outflowing dye forming couplers is so complex that it is not few that the production cost thereof is high.